VDPAU support

When the front end is running, mythfrontend.real runs at about 3-7%
CPU, with Intel(R) Core(TM)2 Duo CPU E7400 @ 2.80GHz. Power
consumption is about 60W when frontend is playing. This may be a bit
high, compared to some of the Silent PC Review numbers below.

Mythbuntu settings 8.04 x64

/etc/asound.conf contains:

pcm.!default {
type hw
card 0
device 1
}

Here are my settings for mythfrontend General Setup.

AUDIO OUTPUT DEVICE = ALSA:default

PASSTHROUGH OUTPUT DEVICE = Default

MAX AUDIO CHANNELS = stereo

UPMIX = passive

X=Enable AC3 to SPDIF Passthrough

X=Enable DTS to SPDIF Passthrough

_=Aggressive Sound Card Buffering

_=Use internal Volume Controls

The max audio channels is set to stereo, the pass through is not
limited to stereo.